The Sensex opened higher at 25,100.90 and shot up further to 25,235.84 before quoting at 25,205.28 at 1000 hours, showing a gain of 198.30 points, or 0.79 per cent, from its last close. The NSE 50-share Nifty also firmed up by 64.60 points, or 0.87 per cent, to 7,518.75 at 1000 hours.